Sewing machine body and method for making the same

ABSTRACT

A method for making a sewing machine includes step of cutting a board into pieces with desired sizes; step of pressing the pieces to have deformation portions to obtain enclosed or semi-enclosed parts; step of welding sides of each of the parts into welding portions so as to obtain frameworks with hollow interiors; step of welding connection plates to the frameworks to form the sewing machine body, and step of final finishing the sewing machine body. The sewing machine body includes a main frame composed of frameworks which are composed of a plurality of sidewalls and each framework includes a hollow interior defined and enclosed by the sidewalls. Connection plates are used to connect the frameworks.

This is a Continuation-In-Part application of applicant's former application with application Ser. No. 10/778,231, filed on Feb. 17, 2004.

FIELD OF THE INVENTION BACKGROUND OF THE INVENTION

A conventional sewing machine body is made by way of iron casting which is heavy. The body is bulky and has a rough surface condition which does not meet the required specification and configuration. Therefore, further processes of machining and surface treatment are required to the body and this takes a lot of labor and time. Aluminum casting is developed to manufacture the sewing machine body within the past thirty years and may obtain a light in weight body. Nevertheless, the cost of the material and the molds is so high that cuts the benefits of the manufacturers.

The latest method for making the sewing machine body is to make an integral body composed of the base, the upright part and the arm from a single plate. The parts of the transmission mechanism in the sewing machine body are supported by flanges in the integral body. The support to the parts is not strong enough to bear the severe vibration and the actions of the moving parts, especially to the transverse force applied to the flanges. The flanges will be bent or deformed by the frequent impact forces coming from the moving parts and the deformation of the flanges affects the position of the needle bar. This results in abnormal impact between the needle bar and the shuttle of the mechanism so that the result of the sewing cannot be satisfied. Besides, the bending and/or deformation of a large-area pressing to a metal plate are difficult to control. In order to obtain a better result, especially for the periphery of the plate and the depth of the base, the pressing actions have to be taken several times.

The present invention intends to provide a method for making the sewing machine body that is composed of three individual parts connected with each other by welding connection plates therebetween so as to have a light and strong sewing machine body. Each part is made by pressing and welding metal boards so as to obtain hollow frameworks which is strong and light in weight.

SUMMARY OF THE INVENTION

The present invention relates to a method for making a sewing machine body comprising:

-   -   step 1: cutting a board into pieces with desired sizes;     -   step 2: pressing the pieces to have deformation portions so as         to obtain enclosed or semi-enclosed parts;     -   step 3: welding sides of each of the parts into welding portions         so as to obtain frameworks with hollow interiors;     -   step 4: welding connection plates to the frameworks to form the         sewing machine body, and     -   step 5: final finishing the sewing machine body.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view to show the sewing machine body that is made by the method of the present invention;

FIG. 2 is an exploded view to show the sewing machine body made by the method of the present invention;

FIG. 3 is a side view to show the sewing machine body made by the method of the present invention;

FIG. 4 shows the welding seams are parallel to the arm;

FIG. 5 shows steps of the method for making the sewing machine body of the present invention;

FIG. 6 shows the items in the steps of the method of the present invention;

FIG. 7 shows another embodiment of the parts of the sewing machine body made by the method of the present invention, and

FIG. 8 shows yet another embodiment of the parts of the sewing machine body made by the method of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 to 3, the sewing machine body 10 of the present invention comprises a main frame 20 which is composed of three frameworks 200 which are used as a first part 21, a second part 22 and a third part 23 for the main frame 20 of the sewing machine body. Each of the three parts 21, 22 and 23 has a hollow interior 201 defined therein so as to reduce the total weight of the frame 20. A plurality of connection plates 30 are used to connect the first part 21 and the second part 22, and the second part 22 and the third part 23 as shown in FIG. 3. The hollow interior 201 can be defined by four sidewalls so that the hollow interior 201 is enclosed by the four sidewalls and forms as a rectangular cross section as shown in FIG. 2. The hollow interior 201 can be defined by three sidewalls and the hollow interior 201 is enclosed by the three sidewalls and forms as a U-shaped cross section as shown in FIG. 7. The hollow interior 201 can also be defined by an H-shaped sidewall and the hollow interior 201 is enclosed by the three sections of the H-shaped sidewall forms as a U-shaped cross section as shown in FIG. 8. The cross section of each of the parts 21, 22, 23 can also be arranged as an oval configuration or a circular configuration. The sidewalls of the framework 200 are made by boards.

The first part 21 which is the longest one of the three parts and is received in a base 11 of the sewing machine body 10. The second part 22 which is the shortest one of the three parts and is received in the upright part 12 which is connected to a top of an end of the first part 21. The third part 23 is then connected to a distal end of the second part 22 and received in the arm 13 of the sewing machine body 10. The three parts 21, 22 and 23 can be connected with each other by welding or bolts. In this embodiment, four connection plates 30 are welded to respective sides of each of the three parts 21, 22, and 23 as shown in FIG. 1. The welding seams 31 are located at the top edge and the bottom edge of each of the connection plates 30.

As shown in FIG. 4, a force “F” will be applied to the distal end of the third part 23 because the movement of the needle of the sewing machine. The welding seams 31 are arranged to be parallel to the third part 23 and perpendicular to the direction of the force “F”, so as to provide support to against the force “F” to prevent the third part 23 from being bent by the force “F”.

The main frame 20 is manufactured by the individual parts 21, 22 and 23 which are easily made in the factory and the interior space 201 in each of the parts 21, 22, 23 effectively reduces the weight of the parts 21, 22, 23. The cost for manufacturing the parts 21, 22, 23 is obviously much less than the conventional methods. Besides, the parts 21, 22, 23 do not need surface treatment and extra machining and they can be connected with each other within a short period of time. The three parts 21, 22, 23 has excellent structural strength which is strong enough to bear the force that applied to the main frame 20.

As shown in FIGS. 5 and 6, the method for making the sewing machine body as disclosed above comprises the following steps:

-   -   step of cutting 41: cutting a board into pieces (50) with         desired sizes;     -   step of pressing 42: pressing the pieces (50) to have         deformation portions (51) so as to obtain enclosed or         semi-enclosed parts;     -   step of welding 43: welding sides of each of the parts into         welding portions (52) so as to obtain frameworks (200) with         hollow interiors (201);     -   step of connection 44: welding connection plates (30) to the         frameworks (200) to form the sewing machine body, and     -   step of final finishing 45: final finishing the sewing machine         body.

By the method, the sewing machine body can be made in mass production and the body is strong and light in weight.

While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention. 

1. A method for making a sewing machine body comprising: step 1: pressing pieces (50) to have deformation portions (51) so as to obtain enclosed or semi-enclosed parts; step 2: welding sides of each of the pieces (50) into welding portions (52) so as to obtain frameworks (200) with hollow interiors (201); step 3: welding the frameworks (200) to form the sewing machine body, and; step 4: final finishing the sewing machine body.
 2. The method as claimed in claim 1, wherein the pieces (50) are made by cutting a board into the pieces (50) with desired sizes.
 3. The method as claimed in claim 1, wherein the sewing machine body includes a main frame (20) composed of a plurality of frameworks (200) and each of the frameworks (200) is composed of a plurality of sidewalls.
 4. The method as claimed in claim 1, wherein one of the hollow interiors (201) is enclosed by four sidewalls which form as a rectangular cross section.
 5. The method as claimed in claim 1, wherein one of the hollow interiors (201) is partially enclosed by three sidewalls which form as a U-shaped cross section.
 6. The method as claimed in claim 1, wherein one of the hollow interiors (201) is partially enclosed by an H-shaped sidewall which forms as a U-shaped cross section.
 7. The method as claimed in claim 4, wherein the frameworks (200) are a first part (21), a second part (22) and a third part (23) of the main frame (20), the first part (21) is received in a base (11) of the sewing machine body (10).
 8. The method as claimed in claim 7, wherein the second part (22) is connected to between the first part (21) and the third part (23), the second part (22) being received in an upright part (12) of the sewing machine body (10).
 9. The method as claimed in claim 8, wherein the third part (23) is received in an arm (13) of the sewing machine body (10).
 10. The method as claimed in claim 7, wherein connection plates (30) are connected to respective sides of the first part (21), the second part (22) and the third part (23).
 11. The method as claimed in claim 10, wherein the connection plates (30) are integrally welded to the first part (21), the second part (22) and the third part (23). 